Re: Fastest method for comparing overlapping times in random time series

To: mathgroup at smc.vnet.net

Subject: [mg64989] Re: Fastest method for comparing overlapping times in random time series

From: "Ray Koopman" <koopman at sfu.ca>

Date: Fri, 10 Mar 2006 05:15:22 -0500 (EST)

References: <dulspn$3an$1@smc.vnet.net>

Sender: owner-wri-mathgroup at wolfram.com

My earlier suggestion didn't work. This does:
List@@IntervalIntersection[IntervalUnion@@Interval/@list1,
IntervalUnion@@Interval/@list2]
{{0,0},{7.97854,7.97952},{23.9643,24.0535},{31.0982,31.1416},
{32.5135,32.547}}
Prince-Wright, Robert G SEPCO wrote:
> I have two lists, list1{ {t1,t1+dt1}, {t2,t2+dt2},..{ti,ti+dti}}, and
> list2, each representing 'time(i)' and corresponding 'time(i) +
> deltatime(i)'. The time(i) values are determined by an exponential
> inter-arrival time model, and the durations are a scaled uniform random
> variable. Both lists are ordered on time(i). You can think of list 1 as
> representing periods when System 1 is not working, and list 2 as the
> periods when System 2 is not working. Example lists are given as Cell
> Expressions below together with code to convert to a ticker-tape Plot
> (you may need to stretch the graphic to see clearly). The challenge is
> to develop a fast method for determining the periods when both Systems
> are not working, i.e. to create a list corresponding to the start and
> finish times of the overlaps.
>
> Thus far I have only managed to use a Do loop which is very slow for long lists!
>
> Bob
>
> [...data snipped...]